Field
Embodiments described herein generally relate to an apparatus for fabricating devices on a substrate. More particularly, embodiments described herein provide an edge ring for supporting a substrate in a processing chamber.
Description of the Related Art
In the processing of substrates, such as semiconductor wafers and display panels, a substrate is placed on a support in a processing chamber while suitable processing conditions are maintained in the processing chamber. For example, a substrate can be heated for either a deposition, etch or other semiconductor fabrication process. During a semiconductor fabrication process, a substrate may be supported by a supporting structure while energy from above or below the substrate is utilized to heat the substrate. In many processing chambers, an edge ring is utilized to protect the substrate supporting structure while processing the substrate.
FIG. 1 schematically illustrates a sectional view of a conventional edge ring 100 used in a semiconductor processing chamber. The supporting structure that supports the substrate and edge ring 100 is not shown. The edge ring 100 has an inner diameter slightly smaller than an outer diameter of a substrate 102 being processed. During processing, an outer edge region 106 of the substrate 102 is disposed above a supporting surface 104 of the edge ring 100 so that the edge ring 100 extends partially below the substrate 102. Thermal energy 110 may be directed to a bottom surface of the substrate 102 below the substrate 102 and the edge ring 100 to heat the substrate 102, for example using heaters embedded in the substrate supporting structure. Plasma 108 and/or a second heat source may be directed to a top surface of the substrate 102 from above the edge ring 100 to further heat the substrate 102.
Conventional edge rings 100, as shown in FIG. 1, can sometimes become too hot, result in warping of the edge ring 100. Warping of the edge ring 100 results in a decrease in tool uptime should the edge ring 100 require replacement, and an increase in particle generation.
Thus, there is a need for an improved edge ring.